Ancillary techniques on direct‐smear aspirate slides

Abstract

Numerous cytologic techniques aimed at effectively acquiring patient material for molecular testing have been proposed. Such techniques are becoming ever more important in an age of personalized medicine. In this commentary, the authors explored some more commonly proposed techniques to aid in the molecular testing of cytologic specimens. These techniques include the use of cell blocks, direct cytologic smears, filter paper storage, frozen samples, and enriched cellular techniques such as ThinPrep and cytospin preparations. Direct‐smeared slides demonstrate excellent preservation of DNA, are easy to prepare, and are amenable to immediate adequacy at the time of the fine‐needle aspiration (FNA) procedure as well as effective subsequent tumor purity estimation. Cell block methods cannot be assessed at the time of FNA and often demonstrate insufficiency, whereas filter paper and frozen techniques do not allow for the direct assessment of the presence and purity of tumor cells in the sample. Direct‐smeared slides are emerging as the most effective preparation and storage medium of cytologic material to be used for molecular testing. Their cost‐effectiveness, ease of use, and reliability have cemented them as the optimal solution for cytopathologists to fulfill the role of providing advanced molecular testing on patient samples. Cancer (Cancer Cytopathol) 2013. © 2012 American Cancer Society.Cytopathologists are expected to have knowledge of the most relevant molecular tests to be performed on cytologic specimens, as well as the best sample preparation methods. Direct‐smeared slides have emerged as a simple and highly effective method for the storage and submission of patient samples for molecular tests.